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  • 1.
    Lundqvist, Tobias
    Linköping University, Department of Electrical Engineering, Computer Vision.
    3D mapping with iPhone2011Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today, 3D models of cities are created from aerial images using a camera rig. Images, together with sensor data from the flights, are stored for further processing when building 3D models. However, there is a market demand for a more mobile solution of satisfactory quality. If the camera position can be calculated for each image, there is an existing algorithm available for the creation of 3D models.

    This master thesis project aims to investigate whether the iPhone 4 offers good enough image and sensor data quality from which 3D models can be created. Calculations on movements and rotations from sensor data forms the foundation of the image processing, and should refine the camera position estimations.

    The 3D models are built only from image processing since sensor data cannot be used due to poor data accuracy. Because of that, the scaling of the 3D models are unknown and a measurement is needed on the real objects to make scaling possible. Compared to a test algorithm that calculates 3D models from only images, already available at the SBD’s system, the quality of the 3D model in this master thesis project is almost the same or, in some respects, even better when compared with the human eye.

  • 2.
    Kihlman, Henrik
    et al.
    Linköping University, Department of Mechanical Engineering. Linköping University, The Institute of Technology.
    Loser, Raimund
    Leica Geosystems AG.
    6DOF metrology-integrated robot control2003Conference paper (Refereed)
    Abstract [en]

    This paper describes ongoing research into Metrology-integrated robot control. The research is a part of an ongoing EU funded aircraft industry project – ADFAST*. The ADFAST project tries to implement the use of industrial robots in low-volume production, high-demand-on-accuracy operations and for dynamic force compensation. To detect and compensate deflection in industrial robots during a process, the robot uses a metrology system. The metrology system supervises the tool center point of the robot as it executes its processes. Leica has recently released a new metrology system; the LTD800, which measures distances with laser interferometry and can simultaneously measure orientation of targets, through photogrammetry, using an additional camera on top of the measuring unit. This paper will describe theory and results from tests performed on integrating the LTD800 with the robot.

  • 3.
    Sundström, Timmy
    et al.
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    Alvandpour, Atila
    Linköping University, Department of Electrical Engineering, Electronic Devices. Linköping University, The Institute of Technology.
    A 4-bit 2.5-GS/s 30-mW Flash ADC in 90nm CMOS2009In: Swedish System on Chip Conference, SSoCC, Arild, May 4-5, Lunds universitet, 2009Conference paper (Other academic)
    Abstract [en]

    A 2.5 GS/s flash ADC, fabricated in 90nm CMOS,avoids traditional power, speed and accuracy trade-offs by usingcomparator redundancy with power-gating capabilities.Redundancy removes the need to control comparator offsets,allowing the large process-variation induced mismatch of smalldevices in nanometer technologies. This enables the use of smallsized,ultra-low-power comparators. Measurement results showthat the ADC dissipates 30 mW at 1.2 V. With 63 gate-ablecomparators, the ADC achieves 4.0 effective number of bits.

  • 4.
    Lindblad, Ulrik
    et al.
    Linköping University, Department of Electrical Engineering.
    Thalin, Patrik
    Linköping University, Department of Electrical Engineering.
    A Behavioral Model of a DSP Processor with Scalable Structure2002Independent thesis Basic level (professional degree)Student thesis
    Abstract [en]

    In mobile digital devices, low power consumption is an important matter to reduce the need for a heavy and big battery. One way of reducing the power consumption is to construct the hardware so that the performance is optimal for the application. The demand of performance is dependent of the tasks that the device will be performing. This is where scalable structure of the hardware is an idea to solve the problem.

    This master thesis serve as a starting point for developing a digital signal processor with scalable structure. The digital signal processor is a common and important part of digital processing. Scalable struture is in this case adding and removing parts of the memory and/or the instruction set, and to make the data wordlength variable. The development is simplified by modeling it on an existing processor. The result of this master thesis is an instruction simulator written in C language. The simulator will be a model for development of the hardware.

  • 5.
    Curescu, C.
    et al.
    Ericsson Research, Torshamnsgatan 23, Kista, 164 83 Stockholm, Sweden.
    Nadjm-Tehrani, Simin
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, RTSLAB - Real-Time Systems Laboratory.
    A bidding algorithm for optimized utility-based resource allocation in ad hoc networks2008In: IEEE Transactions on Mobile Computing, ISSN 1536-1233, Vol. 7, no 12, 1397-1414 p.Article in journal (Refereed)
    Abstract [en]

    This paper proposes a scheme for bandwidth allocation in wireless ad hoc networks. The quality-of-service (QoS) levels for each end-to-end flow are expressed using a resource-utility function, and our algorithms aim to maximize aggregated utility. The shared channel is modeled as a bandwidth resource defined by maximal cliques of mutual interfering links. We propose a novel resource allocation algorithm that employs an auction mechanism in which flows are bidding for resources. The bids depend both on the flow's utility function and the intrinsically derived shadow prices. We then combine the admission control scheme with a utility-aware on-demand shortest path routing algorithm where shadow prices are used as a natural distance metric. As a baseline for evaluation, we show that the problem can be formulated as a linear programming (LP) problem. Thus, we can compare the performance of our distributed scheme to the centralized LP solution, registering results very close to the optimum. Next, we isolate the performance of price-based routing and show its advantages in hotspot scenarios, and also propose an asynchronous version that is more feasible for ad hoc environments. Further experimental evaluation compares our scheme with the state of the art derived from Kelly's utility maximization framework and shows that our approach exhibits superior performance for networks with increased mobility or less frequent allocations. © 2008 IEEE.

  • 6.
    Hallander, Ingrid
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    A broad perspective on life cycle considerations in product development2004Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    For products with long life cycles, operational and support costs represent a significant part of the total cost for the product. Moreover, such products frequently tend to be complex and contain a mixture of both mature. stable technology with bng life cycles and new technology with short life cycles. lt is therefore of great interest to industry to determine how to take these factors into consideration in an efficient way during product development.

    Another factor that affects product development for these and other kinds of products with shorter life cycles is interest in taking a wider view of the end-user or customer scenario, for instance by offering support and after sales services for the products. All these interests drive the demand to consider life cycle related issues in product development, not just life cycle cost. This also makes a life cycle perspective interesting for fums that produce products with shorter life cycles than the ones studied here through the opportunity for after market sales and services.

    This research has been explorative, aiming to understand how firms manage to take life cycle related demands into consideration during product development. The aim was to expand from a cost oriented focus to a wider focus, a value oriented focus, here called life cycle value. The dominant question has been "how" life cycle related demands are considered, focusing on barriers to and enablers for this. Equally important has been to determine the implication of life cycle value for different firms and industries and to find out where value is added in product development. A combination of a quantitative and qualitative research approach has been used to collect empirical data.

    One important finding was that there is an interest to deliver a solution to the customer rather than just a product, to consider customer revenue. This adds a new perspective to the implication of life cycle value, moving from a life cycle cost scenario to a life cycle cost versus revenue scenario. The results fom cases were categorized into six main attributes. These attributes were considered to be very influential and important for the ability to take life cycle perspective into account during product development.

    • Holistic Perspective
    • Requirements & Metrics
    • Leadership & Management/Knowledge management
    • Tools & Methods
    • Organizational Factors
    • Enterprise Relationships

    Within each of these attributes, several practices and lessons learned were identified. Some of the results are also worth investigating further in continued research:

    • Requirements formulation and management is considered to be critical. Well defined and clearly stated demands are key to taking life cycle issues into account due to the difficulty of incorporating life cycle related demands into the product. Nonetheless, balancing these demands against others is perceived to be difficult, and there is a clear need for tools, methods or models to support decision-making in this context.
    • The incorporation of new technology and services is another field of interest to industry. Organizational support and planning for technology insertion and new innovations and services into existing products and product lines are needed.
    • The organizational support to balance specialization and integration in a product development context, with a long-term focus
    • The effect of a transfer from delivering a product to delivering product and support services to the organization.
    List of papers
    1. Life cycle value in product development: a case study in the transportation industry
    Open this publication in new window or tab >>Life cycle value in product development: a case study in the transportation industry
    2003 (English)In: DS 31: Proceedings of ICED 03, the 14th International Conference on Engineering Design, Stockholm, Stockholm, Sweden: ICED'03 , 2003, 417-418 p.Conference paper, Published paper (Other academic)
    Abstract [en]

    Several factors prevent enterprises from having a holistic perspective during product development. Important aspects include increased product complexity and significant uncertainty with regard to technology. For products with a long life cycle this is extremely important since development and life cycle costs are high. The combination of complexity of system design and the limits of individual human comprehension typically make it difficult to envision a best value solution.

    In an attempt to encircle a more holistic perspective of value, the concept of Life Cycle Value has evolved within the Lean Aerospace Initiative, LAI. The implication of this is development of products incorporating life cycle and long-term focus including cost and performance and reliability factors. A similar perspective has evolved within the Lean Aircraft Research Program, LARP, in Sweden.

    This paper contributes a new study of how life cycle aspects are taken into consideration in a large corporation in the transportation industry. The purpose of the research was to examine relative contributions to product development and determine factors that significantly promote the ability to consider the life cycle perspective. The results will be discussed with respect to tools, methods, requirements, metrics, leadership and other organizational factors, innovation, and enterprise relationships.

    Place, publisher, year, edition, pages
    Stockholm, Sweden: ICED'03, 2003
    Keyword
    Life cycle, value, product development, transportation industry
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-36398 (URN)31246 (Local ID)1-904670-00-8 (ISBN)31246 (Archive number)31246 (OAI)
    Conference
    ICED 03, the 14th International Conference on Engineering Design, Stockholm
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2013-12-03
    2. Lifecycle value framework for tactical aircraft product development
    Open this publication in new window or tab >>Lifecycle value framework for tactical aircraft product development
    2001 (English)Conference paper, Published paper (Other academic)
    Abstract [en]

    Due to a dramatic reduction in defense procurement, the benchmark for developing new defense systems today is performance at an affordable cost. In an attempt to encircle a more holistic perspective of value, lifecycle value has evolved as a concept within the Lean Aerospace Initiative, LAI. The implication of this is development of products incorporating lifecycle and long-term focus instead of a shortsighted cost cutting focus. The interest to reduce total cost of ownership while still improving performance, availability, and sustainability, other dimensions taken into account within the lifecycle value approach, falls well within this context. Several factors prevent enterprises from having a holistic perspective during product development. Some important aspects are increased complexity of the products and significant technological uncertainty. The combination of complexity in system design and the limits of individual human comprehension typically prevent a best value solution to be envisioned. The purpose of this research was to examine relative contributions in product development and determine factors that significantly promote abilities to consider and achieve lifecycle value. This paper contributes a maturity matrix based on important practices and lessons learned through extensive interview based case studies of three tactical aircraft programs, including experiences from more than 100 interviews.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-102199 (URN)
    Conference
    2001 Eleventh Annual International Symposium, Melbourne, Australia, 1-5 July 2001
    Available from: 2013-12-03 Created: 2013-12-03 Last updated: 2013-12-03
  • 7.
    Wallsten, Björn
    et al.
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, The Institute of Technology.
    Johansson, Nils
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, The Institute of Technology.
    Krook, Joakim
    Linköping University, Department of Management and Engineering, Environmental Technology and Management. Linköping University, The Institute of Technology.
    A Cable Laid Is a Cable Played: On the Hibernation Logic behind Urban Infrastructure Mines2013In: The Journal of urban technology, ISSN 1063-0732, E-ISSN 1466-1853, Vol. 20, no 3, 85-103 p.Article in journal (Refereed)
    Abstract [en]

    Our societies are reliant on metals to such an extent that the total amounts of some of them in the built environment are comparable in size to the remaining amounts in known mountain ores. Because of concerns about mineral scarcity, the United Nations has assessed alternative sources for metal extraction and targeted urban areas in general and infrastructure systems in particular, since these are large, spatially concentrated and rich in metals. Referring to the possibility of recovering these metal stocks, infrastructure systems constitute what material flow researchers has conceptually termed “urban mines.” While most urban infrastructure is in use, significant amounts of cables and pipes have been disconnected and remain in their subsurface locations; they are “hibernating.” In this article, we analyze the occurrence of such hibernation in the Swedish city of Norrköping's urban infrastructure mine where, we know from a previous study, that every fourth kilo of infrastructure is discarded. Our applied perspective is different from the logic of system expansion as a way to meet increased demand often found in the field of infrastructure studies since we are interested in how systems are disconnected and left behind. This enables us to offer a refined understanding of the concepts of infrastructure “decline” and infrastructure “cold spots.” We argue that to prevent the increase of dormant infrastructures and to engage in the urban mining of already dormant infrastructures, we must develop a sensibility to the materiality of derelict infrastructure components and the underlying causes for why they form different kinds of spatial patterns.

  • 8.
    Bernfort, Lars
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Health Sciences.
    Eckard, Nathalie
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Health Sciences.
    Husberg, Magnus
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Health Sciences.
    Alwin, Jenny
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Health Sciences.
    A case of community-based fall prevention: Survey of organization and content of minor home help services in Swedish municipalities2014In: Scandinavian Journal of Public Health, ISSN 1403-4948, E-ISSN 1651-1905, Vol. 42, no 7, 643-8 p.Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The aim of this study was to survey minor home help services provided by Swedish municipalities with the main purpose to prevent fall injuries.

    METHODS: If minor home help services were presented on the homepage of a municipality, an initial telephone contact was taken. Thereafter a questionnaire was administered, including questions about target groups, aim with the services, tasks included, costs and restrictions for users, budget, and experienced gains with the services. Municipalities not providing minor home help services were asked about the reason therefore and if the municipality had previously provided the services Results: The questionnaire response rate was 92%. In 191 of Sweden's 290 municipalities services were provided by, or in cooperation with, the municipality. Reasons for not providing the services were mainly financial and lack of demand. Services were more often provided in larger cities and in municipalities located in populous regions. In some municipalities services were performed by persons with functional disabilities or unemployed persons. CONCLUSIONS: BOTH PROVIDERS AND USERS EXPRESSED SATISFACTION WITH THE SERVICES ASPECTS EXPRESSED WERE THAT SERVICES LEAD TO GREATER SENSE OF SAFETY AND SOCIAL GAINS THE EFFECT OF THE SERVICES IN TERMS OF FALL PREVENTION IS YET TO BE PROVED WITH ONLY A SMALL FALL-PREVENTIVE EFFECT SERVICES ARE PROBABLY COST-EFFECTIVE IMPROVED QUALITY OF LIFE, SENSE OF SAFETY, AND BEING ABLE TO OFFER MEANINGFUL WORK TO OTHERWISE UNEMPLOYED PERSONS ARE IMPORTANT ASPECTS THAT MIGHT IN THEMSELVES MOTIVATE THE PROVISION OF MINOR HOME HELP SERVICES.

  • 9.
    Eliasson, Karolina
    Linköping University, Department of Computer and Information Science, CASL - Cognitive Autonomous Systems Laboratory. Linköping University, The Institute of Technology.
    A case-based approach to dialogue systems2010In: Journal of experimental and theoretical artificial intelligence (Print), ISSN 0952-813X, E-ISSN 1362-3079, Vol. 22, no 1, 23-51 p.Article in journal (Refereed)
    Abstract [en]

    We describe an approach to integrate dialogue management, machine-learning and action planning in a system for dialogue between a human and a robot. Case-based techniques are used because they permit life-long learning from experience and demand little prior knowledge and few static hand-written structures. This approach has been developed through the work on an experimental dialogue system, called CEDERIC, that is connected to an unmanned aerial vehicle (UAV). A single case base and case-based reasoning engine is used both for understanding and for planning actions by the UAV. Dialogue experiments both with experienced and novice users, where the users have solved tasks by dialogue with this system, showed very adequate success rates.

  • 10.
    Wetterö, Jonas
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Rheumatology . Linköping University, Faculty of Health Sciences.
    Pettersson, Sofia
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Surgery .
    Holmgren Peterson, Kajsa
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    A cellular imaging CDIO project for 2nd semester students in engineering biology2006In: World Transactions on Engineering and Technology Education, ISSN 1446-2257, Vol. 5, no 2, 279-282 p.Article in journal (Refereed)
    Abstract [en]

    The demand for exact engineering within the life sciences is growing and the Engineering Biology programme at Linköping University, Linköping, Sweden, prepares students for a career at this interface. Conceive – Design – Implement – Operate (CDIO) was recently pioneered in an introductory project course. Groups of six to seven students apply a LIPS scalable project model from traditional engineering educational environments on, for example, a cellular imaging task in a hospital setting, prior to taking courses in cell biology/optics. Besides facilitating the implementation of CDIO in higher courses, students gain early career insight and enhance their communication skills. A customer (senior teacher) needs to visualise structures in cells, and the student group is contracted to deliver an applied and optimised method to meet specified requirements. The customer reviews deliverables before the tollgates and communicates with the student project leader. Other students are responsible for documentation and subsystems. The project is allocated laboratory facilities and hardware, and two fictitious subcontractors supply samples and consumables. Extra teachers perform supervision and methodological consultation. In summary, CDIO is indeed applicable and rewarding in cellular imaging, yet is also challenging.

  • 11.
    Nordgren, Anders
    Linköping University, Department of Culture and Communication, Centre for Applied Ethics. Linköping University, Faculty of Arts and Sciences.
    A climate tax on meat?2012In: Climate change and sustainable development :: ethical perspectives on land use and food production: ethical perspectives on land use and food production / [ed] Thomas Potthast, Simon Meisch, Wageningen: Wageningen Academic Publishers, 2012, 109-114 p.Conference paper (Other academic)
    Abstract [en]

    Climate change is a major framing condition for sustainable development of agriculture and food. Global food production is a major contributor to global greenhouse gas emissions and at the same time it is among the sectors worst affected by climate change. This book brings together a multidisciplinary group of authors exploring the ethical dimensions of climate change and food. Conceptual clarifications provide a necessary basis for putting sustainable development into practice. Adaptation and mitigation demand altering both agricultural and consumption practices. Intensive vs. extensive produc.

  • 12.
    Westerlund, Andreas
    et al.
    Linköping University, Department of Mathematics. Linköping University, The Institute of Technology.
    Göthe-Lundgren, Maud
    Linköping University, Department of Mathematics. Linköping University, The Institute of Technology.
    Larsson, Torbjörn
    Linköping University, Department of Mathematics. Linköping University, The Institute of Technology.
    A column generation scheme for the fixed fleet heterogeneous vehicle routing problem2005Report (Other academic)
    Abstract [en]

    We present an optimizing column generation procedure for solving the vehicle routing problem with a fixed heterogeneous fleet of vehicles; if the method is used in a truncated fashion it turns into a heuristic. The method is based on a new mathematical formulation, which includes a new type of valid inequalities, strengthened by the use of Chvátal-Gomory rounding, and a Lagrangian dualization of this formulation. The dual problem is attacked by subgradient optimization and a near-optimal dual solution obtained is used for enumerating routes that are promising candidates for being used in an optimal solution. These routes are collected in a set partitioning problem, which is finally solved, and an upper bound to the optimal objective value is obtained. The method is evaluated on a set of small-scale test instances. The valid inequalities improves the lower bound significantly: the improvement depends on the ratio between total customer demand and total vehicle capacity. The qualities of the upper bounds varies quite much among the instances.

  • 13.
    Gunnarsson (Lidestam), Helene
    et al.
    Linköping University, Department of Mathematics, Optimization . Linköping University, The Institute of Technology.
    Rönnqvist, Mikael
    Linköping University, Department of Mathematics, Optimization . Linköping University, The Institute of Technology.
    Carlsson, Dick
    Södra Cell AB, Växjö, Sweden.
    A combined terminal location and ship routing problem2006In: Journal of the Operational Research Society, ISSN 0160-5682, Vol. 57, no 8, 928-938 p.Article in journal (Refereed)
    Abstract [en]

    In this paper, we consider a combined terminal location and ship routing problem at Södra Cell AB. The purpose is to supply the customers' annual demand for pulp products while minimizing the distribution costs. Customers are supplied with various pulp products from pulp mills in Scandinavia by ships, trains, or lorries. The ship routes go from the pulp mills to terminals in Europe. From each terminal, the products are transported to customers by lorry, train, or barge. Some customers can be supplied directly from the pulp mills by trains or lorries. We have developed a mathematical model to select which terminals to use and, at the same time, determine the shipping routes. The mixed integer programming model was solved directly using a commercial solver. When the number of routes generated is large, the time required to obtain an optimal solution is too long. Hence, we have developed heuristics in order to obtain an acceptable solution in reasonable time. In addition to the basic case, five different scenarios were tested. Our heuristics provide solutions that are within 0.12% of the optimal ones.

  • 14.
    Almkvist, Per
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    A comparison of two line capacity models for railway traffic2006Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    There are a lot of different factors that affect the capacity on our railways. The infrastructure is one important part but also the timetable and the mixture of trains affect the capacity. The performance on the stations is of course a very important part of the railway system. In this report line capacity models are studied and the purpose of the models is to estimate the capacity on the track between the stations. The models that are studied in the report are the UIC-model and Banverkets model for line capacity. The UIC-model is developed by the European organization with the name UIC and aim to create a more common interpretation of line capacity in central Europe. The model from Banverket is used to give a first indication when seeking problem areas in the railway system. Both models gives a percentage use of the capacity witch is calculated by dividing the time that the track is occupied with the time that is studied. Afterwards the capacity consumption is compared to predefined values that give information about the traffic situation on the line. Also the restore ability is being examined in the report. The measure is based on the delay situation on the specific line.

    The UIC-model is more complex compared to Banverkets model. The UIC-model demand more information that describes the infrastructure and the vehicles. Also the user needs a simulation program to get the necessary information about the reservations of the block sections. The model from Banverket is easier to use but at the same time not as clear as the UIC-model. There is an obvious relation between the models stronger and weaker sides and there purposes.

    The line capacity models and the restore ability are used in a case at the line between Uppsala – Myrbackan (north of Stockholm). Two timetables from the autumn of 2004 and the autumn of 2006 are used in the case. The weekdays that are studied are Tuesday, Wednesday and Thursday. The line is being used the most at the time between 07.00 and 09.00, this is the time that are studied in the case. The results from the case are a bit contradictory. The line capacity models indicated no overload, at the same time the restore ability shows that the mount of delays increases on the line.

  • 15.
    Karlsson, Fredrik
    et al.
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    Moshfegh, Bahram
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, The Institute of Technology.
    A comprehensive investigation of a low-energy building in Sweden2007In: Renewable Energy, ISSN 0960-1481, Vol. 32, no 11, 1830-1841 p.Article in journal (Refereed)
    Abstract [en]

    In Sweden, the building sector alone accounts for almost 40% of the total energy demand and people spend more than 80% of their time indoors. Reducing energy demand in the buildings is essential to the achievement of a sustainable built environment. At the same time, it is important to not deteriorate people's health, well-being and comfort in buildings. Thus, designing healthy and energy efficient buildings are one of the most challenging tasks for building scientists. A low-energy building that uses less than half of the purchased energy of a comparable typical Swedish building has been investigated from different viewpoints in an attempt to represent the building at different system levels. First, the ventilation performance in different rooms using the tracer gas method is reported. Second, results from simulations and in situ measurements are used to analyse the building's power demand and energy performance. The household's behaviour and their impact on energy usage as well as acceptance are reported. Finally, the CO2 emissions with regard to the energy usage are analysed on the basis of different supply energy forms from surrounding energy systems, for example a Swedish and European electricity mix, or district heating as a substitute for electrical heating.

  • 16.
    Wenchert, Jonn
    Linköping University, Department of Management and Engineering, Logistics & Quality Management.
    A Contemporary Six Sigma and Lean Integration: Towards the Ideal State2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A new reality, where human labor is replaced by automated machines is causing production management to rethink how they can steer the production to meet their customers demand. There is a gap of values, techniques and tools to communicate with the processes existing in the new modern factories, where data sometimes is the single output. This thesis purpose was to develop a model out of Lean and Six Sigma, as an answer to how modern factory could work with an information system, reaching the ideal state.

     

    Through a theoretical analysis, Lean and Six Sigma differences in values, techniques and tools were weighted by the ideal state and recommendations from literature. Through a unstructured interview and system design review with a logistic group at a Swedish Modern Factory (SMF) a concept of an information system was developed. A project to test the model was initialized, where Define, Measure and Analyze phase was conducted. The model was thereafter modified from the projects implications.

     

    The result was a Lean Six Sigma model which values are customer focus, ideal state, result orientation, committed leadership, education and involvement. The technique follow a DMAIC cycle and continuous improvements through a current to future state approach. The used techniques were considered Six Sigma heavy, where Leans principles are considered into the models values. The information system supports the model in setting the processes of the factory in either stability or potential state, where they differ in Measure and Analyze phase. The test at SMF developed several assignable causes to variation on the component As lead time. The model adapted after the test to involve a Measurement System Analysis (MSA), before setting the next current state of the process.

  • 17.
    Lundin, Rolf A.
    et al.
    Jönköping International Business School, Jönköping, Sweden.
    Sundin, Elisabeth
    Linköping University, Department of Management and Engineering, Business Administration. Linköping University, Faculty of Arts and Sciences.
    A Dark Side ofInternationalization2013In: Final Program and Abstracts / [ed] Lars Engvall, Antti Alanamo and Kerstin Sahlin, 2013Conference paper (Other academic)
    Abstract [en]

    The importance of internationalization for Sweden has for a long time been hot on the political agenda. The academic field is part of a strong support of internationalization ambitions. But there are degenerate species of internationalization to keep a sharp eye on. One we have in mind concerns how applicants for academic positions are evaluated.

    Part of this internationalization is that publications in international journals (mostly American or British) are expected to be the prime criteria in evaluation for academic positions. Evaluations also seem to be transformed into a mathematical exercise where content in fact does not count, but only the numbers of publications and the rankings of the journals. A similar trend is the demand for international evaluators of all parts of our national system which is research programs, applications for financial resources for research programs, projects and positions. International is also when it comes to these matters almost equated with experts from the US orwestern Europe even though the academic landscape is transformed worldwide.

    We question this trend: Is quality promoted in this way? Scandinavian/Nordic systems have qualities that are worth protecting. We will elaborate on our standpoints and give some examples from our own experiences as evaluators and experts.

    We will also argue that the methods used by many international colleagues could be seen as part of a devaluation of the professional academic system. Unfortunately, we expect the methods used to be the standard in the years to come.

  • 18.
    Palm, Elin
    Linköping University, Department of Culture and Communication, Centre for Applied Ethics. Linköping University, Faculty of Arts and Sciences.
    A Declaration of Healthy Dependence: The case of home care2014In: Health Care Analysis, ISSN 1065-3058, E-ISSN 1573-3394, Vol. 22, no 4, 385-404 p.Article in journal (Refereed)
    Abstract [en]

    Aging populations have become a major concern in the developed world and are expected to require novel care strategies. Public policies, health-care regimes and technology developers alike stress the need for a more individualized care to meet the increased demand for care services in response to demographic change. Increasingly, care services are offered to individuals with diseases and or disabilities in their homes by means of Personalized Health-Monitoring (PHM) technologies. PHM-based home care is typically portrayed as the key to a cost-effective future care that better can accommodate the needs of an aging population and promote care recipients’ independence. In light of the emerging technology-based home care, this article sets forth to investigate the significance and implications of a strong emphasis on independence in relation to this novel care form. Notions of independence as used by care planners, care providers and technology developers are examined in relation to ICT-based home care and the reasonableness of independence as an aim for future health-care is critically discussed. In conclusion, the need for a shift from a strong emphasis on independence to a right to healthy dependence is advocated.

  • 19.
    Nordberg, Klas
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Computer Vision.
    Doherty, Patrick
    Linköping University, The Institute of Technology. Linköping University, Department of Computer and Information Science, KPLAB - Knowledge Processing Lab.
    Forssén, Per-Erik
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Computer Vision.
    Wiklund, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Computer Vision.
    Andersson, Per
    A flexible runtime system for image processing in a distributed computational environment for an unmanned aerial vehicle2006In: International Journal of Pattern Recognition and Artificial Intelligence, ISSN 0218-0014, Vol. 20, no 5, 763-780 p.Article in journal (Refereed)
    Abstract [en]

    A runtime system for implementation of image processing operations is presented. It is designed for working in a flexible and distributed environment related to the software architecture of a newly developed UAV system. The software architecture can be characterized at a coarse scale as a layered system, with a deliberative layer at the top, a reactive layer in the middle, and a processing layer at the bottom. At a finer scale each of the three levels is decomposed into sets of modules which communicate using CORBA, allowing system development and deployment on the UAV to be made in a highly flexible way. Image processing takes place in a dedicated module located in the process layer, and is the main focus of the paper. This module has been designed as a runtime system for data flow graphs, allowing various processing operations to be created online and on demand by the higher levels of the system. The runtime system is implemented in Java, which allows development and deployment to be made on a wide range of hardware/software configurations. Optimizations for particular hardware platforms have been made using Java's native interface.

  • 20.
    Gutes, A.
    et al.
    Gutés, A., Sensors and Biosensors Group, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Spain.
    Cespedes, F.
    Sensors and Biosensors Group, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Spain.
    del, Valle M.
    del Valle, M., Sensors and Biosensors Group, Department of Chemistry, Autonomous University of Barcelona, Edifici Cn, 08193 Bellaterra, Spain.
    Louthander, D.
    Krantz-Rülcher, Christina
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Winquist, Fredrik
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    A flow injection voltammetric electronic tongue applied to paper mill industrial waters2006In: Sensors and actuators. B, Chemical, ISSN 0925-4005, Vol. 115, no 1, 390-395 p.Article in journal (Refereed)
    Abstract [en]

    A voltammetric electronic tongue with automated operation based on the flow injection (FIA) technique was applied to the characterization of wastewaters coming from the paper mill industry. A metallic multielectrode array - formed by platinum, gold and rhodium electrodes - was employed as the detection system, while the measurements were based on large amplitude pulse voltammetry (LAPV). LAPV consisted in scans of pulses from to 0 to 1.8 V at 0.2 V steps. Five current values were recorded for each pulse, so a set of 300 current values (three electrodes × 20 pulses × five values) was recorded for each sample. Samples were first discriminated using Principal Component Analysis (PCA), while Artificial Neural Networks were used for the characterization and prediction of chemical oxygen demand, conductivity and pH. The system may be used for the quick identification and monitoring of the quality of used waters in these industrial facilities. © 2005 Elsevier B.V. All rights reserved.

  • 21.
    Häll, Carl Henrik
    Linköping University, Department of Science and Technology. Linköping University, The Institute of Technology.
    A Framework for Evaluation and Design of an Integrated Public Transport System2006Licentiate thesis, monograph (Other academic)
    Abstract [en]

    Operators of public transport always try to make their service as attractive as possible, to as many persons as possible and in a so cost effective way as possible. One way to make the service more attractive, especially to elderly and disabled, is to offer door-to-door transportation. The cost for the local authorities to provide this service is very high and increases every year.

    To better serve the needs of the population and to reduce the cost for transportation of elderly and disabled, public transportation systems are evolving towards more flexible solutions. One such flexible solution is a demand responsive service integrated with a fixed route service, together giving a form of flexible public transport system. The demand responsive service can in such a system be used to carry passengers from their origin to a transfer location to the fixed route network, and/or from the fixed route network to their destination.

    This thesis concerns the development of a framework for evaluation and design of such an integrated public transport service. The framework includes a geographic information system, optimization tools and simulation tools. This framework describes how these tools can be used in combination to aid the operators in the planning process of an integrated service. The thesis also presents simulations made in order to find guidelines of how an integrated service should be designed. The guidelines are intended to help operators of public transport to implement integrated services and are found by evaluating the effects on availability, travel time, cost and other service indicators for variations in the design and structure of the service.

    In a planning system for an integrated public transport service, individual journeys must in some way be scheduled. For this reason the thesis also presents an exact optimization model of how journeys should be scheduled in this kind of service.

  • 22.
    Noroozi, Sayeh
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    A Framework for Sales and Operations Planning in Process Industries2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis studies Sales and Operations Planning (S&OP) in process industries. S&OP is a planning process which has a role of balancing demand and supply at an aggregate level. S&OP has traditionally been considered as a generic process meaning that it is independent from the context of the industry in which it is implemented. Process industries do; however, have specific characteristics which affect their planning and control processes, including S&OP. Therefore, the aim in this thesis is to reconcile these two contradictory stances and furthermore investigate how the specific properties in process industries should be included into an S&OP framework. Such a differentiated framework aims to support process industries to design/implement their S&OP process based on their unique requirements in relation to their markets, products and processes while it also takes into account the specific characteristics regarding the continuous production. Consequently, the process industries would realize the expected benefits from S&OP process to a greater extent.

    The study starts with a literature review on S&OP in process industries in order to build the knowledge foundation for subsequent studies. The results show that the underlying difference between process industries and discrete industries is the object continuity which affects the selection of production processes including resources. Thus, process industries are often hybrids in the sense that their production processes include both continuous production, when the transformed object (material) is continuous, and discrete production when the object (material) turns into discrete products after the discretization point. In other words, process industries deploy both continuous production and discrete production while discrete industries use only discrete production. The specific characteristics of process industries are actually related to the continuous production part and influence the planning processes as well. As the result of this study, the continuous production characteristics that can affect the S&OP process are identified.

    In the continuation of the thesis and in order to provide a typology for planning and control purposes, the object type (continuous and discrete) is combined with two other dimensions i.e. mode type (onetime, intermittent and continuous) and driver type (customer order driven and forecast driven) into a planning and control typology. The mode type addresses the repetitivity of the flow and the driver type takes into account the trigger of the flow. Each dimension has a transition point – i.e. the discretization point for the object type, mode interface point for the mode type and customer order decoupling point for the driver type – and represents a hybrid situation since different production environments are required before and after each transition point. The typology aims to illustrate how each dimension affects the planning and control issues as well as how the dimensions are interrelated and how this combination influence the managerial decisions. The typology integrates the concepts from both process industries and discrete industries and thus, is applicable for both.

    Thereafter the typology is applied to the S&OP process and an integrated framework is suggested based on the three dimensions with specific focus on process industries. In this framework, the effects of hybridities within each dimension and cross-hybridities between the dimensions on the S&OP process are also considered. The importance of hybridities and cross-hybridities lies in the fact that the planning of the hybrid systems is a complex task due to the varying managerial decisions before and after the transition points. Finally, implementation steps for the suggested S&OP framework are outlined for the process industries in order to position themselves in the framework, identify the implementing procedures, and obtain potential benefits based on the differentiated S&OP process.

    List of papers
    1. Sales and operations planning in the process industry: A literature review
    Open this publication in new window or tab >>Sales and operations planning in the process industry: A literature review
    2017 (English)In: International Journal of Production Economics, ISSN 0925-5273, E-ISSN 1873-7579, Vol. 188, 139-155 p.Article in journal (Refereed) Published
    Abstract [en]

    This paper provides a systematic literature review of Sales and Operations Planning (S&OP) in process industries. The aim is to investigate the present state of S&OP in process industries in comparison to discrete manufacturing industries and to identify the desired future state of the S&OP process based on the specific characteristics of process industries. The findings of this paper show that this issue has not received much attention in the academic world. Hence there is a need for conceptual models with focus on process industries’ specific characteristics. Process industries are actually hybrids of continuous production and discrete production (respectively, upstream and downstream of the discretization point) and the specific characteristics of process industries are related to the continuous production part. Thus, in this paper, the characteristics upstream of the discretization point are investigated and the integration of them in the S&OP process of the process industries is stressed.

    Place, publisher, year, edition, pages
    Elsevier, 2017
    Keyword
    Sales and operations planning, Process industry, Discretization point
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-106705 (URN)10.1016/j.ijpe.2017.03.006 (DOI)000401381300013 ()
    Note

    The original title in manuskript fiorm of this article was Sales and operations planning in the process industry.

    Funding agencies: Swedish Foundation for Strategic Research (SSF)

    Available from: 2014-05-19 Created: 2014-05-19 Last updated: 2017-06-13Bibliographically approved
    2. A modularised typology for flow design based on decoupling points - a holistic view on process industries and discrete manufacturing industries
    Open this publication in new window or tab >>A modularised typology for flow design based on decoupling points - a holistic view on process industries and discrete manufacturing industries
    2016 (English)In: Production planning & control (Print), ISSN 0953-7287, E-ISSN 1366-5871, Vol. 27, no 16, 1344-1355 p.Article in journal (Refereed) Published
    Abstract [en]

    Management of production activities covers a wide range of decisions. In this paper, a modularised approach is suggested that, through configuration, generates a case-specific flow design. The approach is based on identification of decision categories that are generic and fundamental in the flow design, covering both discrete manufacturing industries and process industries. Each decision category identifies a unique property of the flow which changes at a particular point: this is termed a decoupling point. A three-dimensional modularised typology is developed by combining three different decision categories. Cases from the steel industry and the tooling industry are used to illustrate how the typology can be applied. The modularised approach provides a typology for the application of both qualitative and quantitative methods for flow management, including planning, control and performance management.

    Place, publisher, year, edition, pages
    TAYLOR & FRANCIS LTD, 2016
    Keyword
    Typology; decoupling point; planning and control; process industry; modularisation
    National Category
    Production Engineering, Human Work Science and Ergonomics
    Identifiers
    urn:nbn:se:liu:diva-132245 (URN)10.1080/09537287.2016.1220649 (DOI)000384468200004 ()
    Note

    Funding Agencies|Swedish Foundation for Strategic Research [PIC-LI]; Process Industrial IT and Automation (PiiA) - VINNOVA; Swedish Energy Agency, Formas; Swedish industry [2014-05110]

    Available from: 2016-10-24 Created: 2016-10-21 Last updated: 2017-04-11
    3. A modularized framework for sales and operations planning with focus on process industries
    Open this publication in new window or tab >>A modularized framework for sales and operations planning with focus on process industries
    2016 (English)In: Production & Manufacturing Research, ISSN 2169-3277, Vol. 4, no 1, 65-89 p.Article in journal (Refereed) Published
    Abstract [en]

    This paper suggests a modularized sales and operations planning (S&OP) framework, consisting of content and process. The framework’s content is based on a typology of decoupling points in which the effect of decoupling points on the decision variables in S&OP is studied. The framework’s process takes a step back and addresses the need for a more elaborate design to precede the operational use of S&OP content for different production contexts. The framework supports both process industries (PIs) and discrete manufacturing industries (DIs), and recognizes their specific requirements and reflects them in their S&OP. The differentiating characteristics of PIs and DIs are emphasized through three different decoupling points, namely: discretization decoupling point, control mode decoupling point, and customer order decoupling point. The suggested framework aims to fill the gap in the literature regarding the lack of aggregate planning processes that match the PIs’ specific requirements by reflecting the differentiating characteristics of PIs in S&OP.

    Place, publisher, year, edition, pages
    Taylor & Francis, 2016
    National Category
    Economics and Business Other Mechanical Engineering Software Engineering
    Identifiers
    urn:nbn:se:liu:diva-133240 (URN)10.1080/21693277.2016.1200502 (DOI)
    Available from: 2016-12-15 Created: 2016-12-15 Last updated: 2017-04-11Bibliographically approved
  • 23.
    Degerman, Pär
    et al.
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Rösth, Marcus
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    Palmberg, Jan-Ove
    Linköping University, Department of Mechanical Engineering, Fluid and Mechanical Engineering Systems. Linköping University, The Institute of Technology.
    A Full Four-Quadrant Hydraulic Steering Actuator Applied to a Fully Automatic Passenger Vehicle Parking System2006In: Proceedings of the 4th FPNI-PhD Symposium, Lafayettem, IN, USA: FPNI Fluid Power Net Publications , 2006, 387-396 p.Conference paper (Refereed)
    Abstract [en]

    This project describes how the Active Pinion hydraulic steering system can be used to replace a electric power steering actuator in the Parking Pilot automatic parking system.

    Customer demand for fully or semi automatic parking systems in passenger cars, are getting higher with increased cost of parking related body damage repair coupled with restricted rearward sight and the larger dimensions of modern cars. This, however, puts new demands on the steering actuator. An automatic parking system requires full control of the steering servo, which is not possible with current hydraulic actuators. Instead these systems have to rely on electric servos which allow for the needed controllability.

    All current electric steering servos have the drawback that it is impossible to use them on anything but small or medium sized cars. Since a parking system can be seen as a premium accessory, which is more likely to attract customers who buy larger cars, this is a major hindrance for the success of automatic parking systems.

    A solution to the problem is to construct a controllable variant of the hydraulic steering servo, the Active Pinion. In this concept a small electric pilot motor is added to the traditional hydraulic valve, which adds one additional degree of freedom to the servo, accomplishing full four-quadrant operations.

    The project discusses how the Active Pinion concept is introduced in the Parking Pilot parking system and how different demands on the parking system relates to the performance of the actuator. The parking system is installed in a prototype car and simulation of the Active Pinion concept is accomplished with HWIL simulation in a load simulator.

  • 24.
    Kling, Daniel
    et al.
    Norwegian Institute Public Heatlh, Norway; Norwegian University of Life Science, Norway.
    Tillmar, Andreas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Egeland, Thore
    Norwegian University of Life Science, Norway; Norwegian Institute Public Heatlh, Norway.
    Mostad, Petter
    Norwegian University of Life Science, Norway; University of Gothenburg, Sweden.
    A general model for likelihood computations of genetic marker data accounting for linkage, linkage disequilibrium, and mutations2015In: International journal of legal medicine (Print), ISSN 0937-9827, E-ISSN 1437-1596, Vol. 129, no 5, 943-954 p.Article in journal (Refereed)
    Abstract [en]

    Several applications necessitate an unbiased determination of relatedness, be it in linkage or association studies or in a forensic setting. An appropriate model to compute the joint probability of some genetic data for a set of persons given some hypothesis about the pedigree structure is then required. The increasing number of markers available through high-density SNP microarray typing and NGS technologies intensifies the demand, where using a large number of markers may lead to biased results due to strong dependencies between closely located loci, both within pedigrees (linkage) and in the population (allelic association or linkage disequilibrium (LD)). We present a new general model, based on a Markov chain for inheritance patterns and another Markov chain for founder allele patterns, the latter allowing us to account for LD. We also demonstrate a specific implementation for X chromosomal markers that allows for computation of likelihoods based on hypotheses of alleged relationships and genetic marker data. The algorithm can simultaneously account for linkage, LD, and mutations. We demonstrate its feasibility using simulated examples. The algorithm is implemented in the software FamLinkX, providing a user-friendly GUI for Windows systems (FamLinkX, as well as further usage instructions, is freely available at www.famlink.se). Our software provides the necessary means to solve cases where no previous implementation exists. In addition, the software has the possibility to perform simulations in order to further study the impact of linkage and LD on computed likelihoods for an arbitrary set of markers.

  • 25.
    Abu Syeed, Kazi
    Linköping University, Department of Computer and Information Science. Linköping University, The Institute of Technology.
    A GIS based Site Suitability Analysis for Shrimp Cultivation in the Coastal Region of Bangladesh2007Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Bangladesh geographically comprised one of the largest delta landscapes of the world. Almost 6.7% of country’stotal area (147570 sqkm.) is covered byrivers and inland water bodies. These water bodies being rich in fishproduction meet the majority of the demand of protein. Bangladesh produces world's fourth largest quantity of fishand it is collected from the inland water bodies. Though shrimps were easily available in the inland water bodies forhundreds of years but shrimp culture as an export-oriented activity is a phenomenon of recent past. Bangladeshearned US$ 2.9 million by exporting shrimp in 1972-73 which was 1 % of the country's total exports. It increased to US$ 33 million in 1980 and to US$ 90.0 million in 1985. But until the mid-1980’s shrimp culture was principallydependent on open-water catches of shrimp it means that time shrimps were not cultivated in a proper planned way.But the culture of shrimp totally for export purpose started after the mid 1980’s. Since then the professional cultivation of shrimp had a very positive and effective impact on the economy of Bangladesh. Exports of shrimpfrom Bangladesh increased from US$ 91 million in FY (Fiscal Year) 1986 to US$ 280 million in FY1997. Duringthe corresponding period, the quantity of shrimp exports increased from 17.2 thousand tonnes to 25.2 thousandtonnes. As most of the shrimp farms have been developed without considering the sustainability of the environmentand some other factors like water pH & salinity, soil pH & salinity, soil texture etc. the farmers are getting lessreturn but affecting the environment most. Geographical Information System (GIS) can give an easier but effectivesolution here through selecting the best suitable sites for shrimp cultivation. Moreover GIS can solve thetransportation problem of this perishable product from the production area to the harbor or airport through transport route selection. This cansave a lot of money and time and consequently make the shrimp cultivation moreeconomic.

  • 26.
    Wang, Daqin
    et al.
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology. Tongji University, Shanghai, China.
    Tang, Ou
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    Huo, Jiazhen
    A heuristic for rationing inventory in two demand classes with backlog costs and a service constraint2013In: Computers & Operations Research, ISSN 0305-0548, Vol. 40, no 12, 2826-2835 p.Article in journal (Refereed)
    Abstract [en]

    We study the rationing policy in an inventory system with two demand classes and different service criteria for backorders. Due to the difference of customer values, system performance sometimes has to be measured with a mixture of penalty cost and service level in managing inventory. With a continuous review (r,Q) system, we develop a critical level rationing policy in which a threshold mechanism is adopted to allocate backorders when multiple outstanding orders exist. Due to the complexity of the problem, a heuristic is developed based on the principle that both demand classes are served with respective target service levels. We also introduce bounds so that the search ranges of decision variables become restrictive. The numerical examples indicate an excellent performance of our heuristic. In addition, when ordering cost is medium or high, the threshold clearing mechanism has the same results as the optimal one. When ordering cost is small (set to zero), different clearing mechanisms should be used depending on the priorities of demand classes. Further analysis indicates that transforming the service constraint into a cost parameter and then applying the existing algorithm will not be a good approach for this problem with mixed performance criteria. It either increases the costs or violates the service constraint. This study also shows the importance of applying rationing policy when high priority class has a low demand volume, target service levels between two classes have a large gap, or replenishment lead time is long. The results of this study should enhance our understanding of how to implement rationing policies in practice.

  • 27.
    Plymoth, Birgitta
    et al.
    Linköping University, Department of Social and Welfare Studies. Linköping University, REMESO - Institute for Research on Migration, Ethnicity and Society. Linköping University, Faculty of Arts and Sciences.
    Reimers, Eva
    Linköping University, Department of Social and Welfare Studies, Learning, Aesthetics, Natural science. Linköping University, Faculty of Educational Sciences.
    A Historical Overview: Care and Education Intersecting with Status and Class in Swedish Childminder Education 1975-20112015In: Nordisk Barnehageforskning, ISSN 1890-9167, E-ISSN 1890-9167, Vol. 9, no 3, 1-16 p.Article in journal (Refereed)
    Abstract [en]

    From a perspective of status and class, this paper delineates changes in Swedish childminder education. The data are policy documents, documents from childminder training, and interviews with educators. The analysis is informed by post-structural theory. The study shows that the status of the childminder program has shifted between high and low status, and led toward differently classed life trajectories at different times. One reason for these variations is that the emphasis in childcare has shifted from care to teaching. This has at times increased the status of the education and the vocation, but also subverted the demand for childminders.

  • 28.
    Flisberg, Patrik
    et al.
    The Forestry Research Institute of Sweden, Uppsala, Sweden.
    Lidén, Bertil
    The Forestry Research Institute of Sweden, Uppsala, Sweden.
    Rönnqvist, Mikael
    The Forestry Research Institute of Sweden, Uppsala, Sweden and Norwegian School of Economics and Business Administration, Bergen, Norway.
    A hybrid method based on linear programming and tabu search for routing of logging trucks2009In: Computers & Operations Research, ISSN 0305-0548, Vol. 36, no 4, 1122-1144 p.Article in journal (Refereed)
    Abstract [en]

    In this paper, we consider an operational routing problem to decide the daily routes of logging trucks in forestry. This industrial problem is difficult and includes aspects such as pickup and delivery with split pickups, multiple products, time windows, several time periods, multiple depots, driver changes and a heterogeneous truck fleet. In addition, the problem size is large and the solution time limited. We describe a two-phase solution approach which transforms the problem into a standard vehicle routing problem with time windows. In the first phase, we solve an LP problem in order to find a destination of flow from supply points to demand points. Based on this solution, we create transport nodes which each defines the origin(s) and destination for a full truckload. In phase two, we make use of a standard tabu search method to combine these transport nodes, which can be considered to be customers in vehicle routing problems, into actual routes. The tabu search method is extended to consider some new features. The solution approach is tested on a set of industrial cases from major forest companies in Sweden.

  • 29.
    Hadera, Hubert
    et al.
    Technical University of Dortmund, Germany.
    Wide, Per
    Linköping University.
    Harjunkoski, Iiro
    ABB Corporate Research, Germany.
    Mäntysaari, Juha
    ABB Oy Industry Solutions, Finland.
    Ekström, Joakim
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering.
    Sand, Guido
    ABB Corporate Research, Germany.
    Engell, Sebastian
    Technical University of Dortmund, Germany.
    A Mean Value Cross Decomposition Strategy for Demand-side Management of a Pulping Process2015In: 12th International Symposium on Process Systems Engineering and 25th European Symposium on Computer Aided Process Engineering / [ed] Krist V. Gernaey, Jakob K. Huusom and Gani Rafiqul, Elsevier , 2015, Vol. 37, 1931-1936 p.Chapter in book (Refereed)
    Abstract [en]

    Energy is becoming a critical resource for process industries as introduction of new policies drive changes in the energy supply systems. Energy availability and pricing is much more volatile. In this study, we propose a Mean Value Cross Decomposition approach to functionally separate production scheduling from energy-cost optimization. Such a decomposition makes it possible to exploit existing optimization solutions avoiding a need to create a new monolithic model. The proposed framework is applied to a continuous process of thermo-mechanical pulping using a discrete-time Resource-Task Network model. Example case study scenarios show that the approach gives optimal system-wide solutions while keeping the models separated.

  • 30.
    Persson, U. Martin
    et al.
    Physical Resource Theory, Chalmers University of Technology, Göteborg, Sweden.
    Henders, Sabine
    Linköping University, Department of Thematic Studies, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences. Linköping University, Department of Thematic Studies, Centre for Climate Science and Policy Research.
    Cederberg, Christel
    Physical Resource Theory, Chalmers University of Technology, Göteborg, Sweden.
    A method for calculating a land-use change carbon footprint (LUC-CFP) for agricultural commodities: applications to Brazilian beef and soy, Indonesian palm oil2014In: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 20, no 11, 3482-3491 p.Article in journal (Refereed)
    Abstract [en]

    The world’s agricultural system has come under increasing scrutiny recently as an important driver of global climate change, creating a demand for indicators that estimate the climatic impacts of agricultural commodities. Such carbon footprints (CFPs), however, have in most cases excluded emissions from land‐use change (LUC) and the proposed methodologies for including this significant emissions source suffer from different shortcomings. Here we propose a new methodology for calculating land‐use change carbon footprints (LUC‐CFPs) for agricultural commodities and illustrate this methodology by applying it to three of the most prominent agricultural commodities driving tropical deforestation: Brazilian beef and soybeans, and Indonesian palm oil. We estimate LUCCFPs in 2010 to be 66 tCO2/tCW for Brazilian beef, 0.9 tCO2/t for Brazilian soybeans, and 8.6 tCO2/t for Indonesian palm oil. The main advantage of the proposed methodology is its flexibility: it can be applied in a tiered approach, using detailed data where it is available while still allowing for estimation of LUC‐CFPs for a broad set of countries and agricultural commodities; it can be applied at different scales, estimating both national and sub‐national LUC‐CFPs; it can be adopted to account both for direct (proximate) and indirect drivers of LUC. It is argued that with an increasing commercialization and globalization of the drivers of land‐use change, LUC‐CFPs could help leverage the power needed to alter environmentally destructive land‐use practices within the global agricultural system by providing a tool for assessing the environmental impacts of production, thereby informing consumers about the impacts of consumption and incentivizing producers to become more environmentally responsible.

  • 31.
    Ekström, Joakim
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A MILP approximation approach for finding optimal toll locations and levels in elastic demand traffic networks2010In: TRANSPORTATION AND URBAN SUSTAINABILITY: Proceedings of the 15th International Conference of Hong Kong Society for Transportation Studies (HKSTS) / [ed] Sumalee, A; Lam, WHK; Ho, HW; Siu, B, Hong Kong, China: Hong Kong Society for Transportation Studies , 2010, 107-114 p.Conference paper (Refereed)
    Abstract [en]

    The toll design problem (TDP) is to find optimal toll locations and corresponding toll levels in a congestion pricing scheme. The TDP can be formulated as a non-convex mathematical program, in which the road users are assumed to be distributed according to a user-equilibrium with elastic demand. This program is hard to solve due to non-convexity and non-smoothness. In this paper, the TDP is approximated by a mixed integer linear program (MILP), in which the non-linear functions of the TDP are approximated by piecewise linear ones. The MILP can be solved to its global optimal solution by known methods, and its optimal solution will give a lower bound on the optimal solution to the TDP. By iteratively updating the MILP approximation, the error introduced by the approximation is reduced, and for a test network with nine nodes and 18 links, the global optimal solution is obtained.

  • 32.
    Holm, Christer
    et al.
    Linköping University, Department of Mathematics.
    Larsson, Andreas
    Linköping University, Department of Mathematics.
    A Model for Multiperiod Route Planning and a Tabu Search Method for Daily Log Truck Scheduling2004Independent thesis Basic level (professional degree)Student thesis
    Abstract [en]

    The transportation cost of logs from forest to customers is a large part of the overall cost for the Swedish forestry industry. Finding good routes from harvesting points to saw and pulp mills is a complex task, where the total number of feasible routes is extremely high. In this thesis we present two methods for log truck scheduling.

    The first is to, from a given set of routes, find the most valuable subset that fulfils the customers demand. We use a model that is similar to the set partitioning problem and a method that is referred to as a composite pricing coupled with Branch and Bound. The composite pricing based method prices the routes (columns) and chooses the most valuable ones that are then added to the LP relaxation. Once an LP optimum is found, the Branch and Bound method is used to find an integer optimum solution. We have tested this on a case of realistic size.

    The second method is a tabu search heuristic. Here, the purpose is to create efficient and qualitative routes from a given number of trips (referred to as predefined trips). From a start solution tabu search systematically generates new solutions. This method was tested on a small problem and on a five times larger problem to study how the size of the problem affected the result. It was also tested and compared on two cases in which the backhauling possibilities (i.e. instead of traveling empty the truck picks up another load on the return trip) had and had not been studied. The composite pricing based method and the tabu search method proved to be very useful for this kind of scheduling.

  • 33.
    Braun, Martin W.
    et al.
    Arizona State University, USA.
    Rivera, Daniel E.
    Arizona State University, USA.
    Stenman, Anders
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A 'Model-on-Demand' Identification Methodology for Nonlinear Process Systems2001In: International Journal of Control, ISSN 0020-7179, E-ISSN 1366-5820, Vol. 74, no 18, 1708-1717 p.Article in journal (Refereed)
    Abstract [en]

    An identification methodology based on multi-level pseudo-random sequence (multi-level PRS) input signals and 'Model-on-Demand' (MoD) estimation is presented for single-input, single-output non-linear process applications. 'Model-on-Demand' estimation allows for accurate prediction of non-linear systems while requiring few user choices and without solving a non-convex optimization problem, as is usually the case with global modelling techniques. By allowing the user to incorporate a priori information into the specification of design variables for multi-level PRS input signals, a sufficiently informative input-output dataset for MoD estimation is generated in a 'plant-friendly' manner. The usefulness of the methodology is demonstrated in case studies involving the identification of a simulated rapid thermal processing (RTP) reactor and a pilot-scale brine-water mixing tank. On the resulting datasets, MoD estimation displays performance comparable to that achieved via semi-physical modelling and semi-physical modelling combined with neural networks. The MoD estimator, however, achieves this level of performance with substantially lower engineering effort.

  • 34.
    Braun, MW
    et al.
    Arizona State Univ, Dept Chem & Mat Engn, Control Syst Engn Lab, Tempe, AZ 85287 USA Linkoping Univ, Dept Elect Engn, Div Automat Control, SE-58183 Linkoping, Sweden.
    Rivera, DE
    Arizona State Univ, Dept Chem & Mat Engn, Control Syst Engn Lab, Tempe, AZ 85287 USA Linkoping Univ, Dept Elect Engn, Div Automat Control, SE-58183 Linkoping, Sweden.
    Stenman, A
    Arizona State Univ, Dept Chem & Mat Engn, Control Syst Engn Lab, Tempe, AZ 85287 USA Linkoping Univ, Dept Elect Engn, Div Automat Control, SE-58183 Linkoping, Sweden.
    A 'Model-on-Demand' identification methodology for non-linear process systems2001In: International Journal of Control, ISSN 0020-7179, Vol. 74, no 18, 1708-1717 p.Article in journal (Refereed)
    Abstract [en]

    An identification methodology based on multi-level pseudo-random sequence (multi-level PRS) input signals and 'Model-on-Demand' (MoD) estimation is presented for single-input, single-output non-linear process applications. 'Model-on-Demand' estimation allows for accurate prediction of non-linear systems while requiring few user choices and without solving a non-convex optimization problem, as is usually the case with global modelling techniques. By allowing the user to incorporate a priori information into the specification of design variables for multi-level PRS input signals, a sufficiently informative input-output dataset for MoD estimation is generated in a 'plant-friendly' manner. The usefulness of the methodology is demonstrated in case studies involving the identification of a simulated rapid thermal processing (RTP) reactor and a pilot-scale brine-water mixing tank. On the resulting datasets, MoD estimation displays performance comparable to that achieved via semi-physical modelling and semi-physical modelling combined with neural networks. The MoD estimator, however, achieves this level of performance with substantially lower engineering effort.

  • 35.
    Svensson, Björn
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology.
    A Multidimensional Filtering Framework with Applications to Local Structure Analysis and Image Enhancement2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Filtering is a fundamental operation in image science in general and in medical image science in particular. The most central applications are image enhancement, registration, segmentation and feature extraction. Even though these applications involve non-linear processing a majority of the methodologies available rely on initial estimates using linear filters. Linear filtering is a well established cornerstone of signal processing, which is reflected by the overwhelming amount of literature on finite impulse response filters and their design.

    Standard techniques for multidimensional filtering are computationally intense. This leads to either a long computation time or a performance loss caused by approximations made in order to increase the computational efficiency. This dissertation presents a framework for realization of efficient multidimensional filters. A weighted least squares design criterion ensures preservation of the performance and the two techniques called filter networks and sub-filter sequences significantly reduce the computational demand.

    A filter network is a realization of a set of filters, which are decomposed into a structure of sparse sub-filters each with a low number of coefficients. Sparsity is here a key property to reduce the number of floating point operations required for filtering. Also, the network structure is important for efficiency, since it determines how the sub-filters contribute to several output nodes, allowing reduction or elimination of redundant computations.

    Filter networks, which is the main contribution of this dissertation, has many potential applications. The primary target of the research presented here has been local structure analysis and image enhancement. A filter network realization for local structure analysis in 3D shows a computational gain, in terms of multiplications required, which can exceed a factor 70 compared to standard convolution. For comparison, this filter network requires approximately the same amount of multiplications per signal sample as a single 2D filter. These results are purely algorithmic and are not in conflict with the use of hardware acceleration techniques such as parallel processing or graphics processing units (GPU). To get a flavor of the computation time required, a prototype implementation which makes use of filter networks carries out image enhancement in 3D, involving the computation of 16 filter responses, at an approximate speed of 1MVoxel/s on a standard PC.

    List of papers
    1. On Geometric Transformations of Local Structure Tensors
    Open this publication in new window or tab >>On Geometric Transformations of Local Structure Tensors
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:liu:diva-13022 (URN)
    Available from: 2008-03-13 Created: 2008-03-13 Last updated: 2010-01-13
    2. Estimation of Non-Cartesian Local Structure Tensor Fields
    Open this publication in new window or tab >>Estimation of Non-Cartesian Local Structure Tensor Fields
    2007 (English)In: Image Analysis: 15th Scandinavian Conference, SCIA 2007, Aalborg, Denmark, June 10-14, 2007 / [ed] Bjarne Kjær Ersbøll, Kim Steenstrup Pedersen, Springer Berlin/Heidelberg, 2007, Vol. 4522/2007, 948-957 p.Conference paper, Published paper (Refereed)
    Abstract [en]

    In medical imaging, signals acquired in non-Cartesian coordinate systems are common. For instance, CT and MRI often produce significantly higher resolution within scan planes, compared to the distance between two adjacent planes. Even oblique sampling occurs, by the use of gantry tilt. In ultrasound imaging, samples are acquired in a polar coordinate system, which implies a spatially varying metric.

    In order to produce a geometrically correct image, signals are generally resampled to a Cartesian coordinate system. This paper concerns estimation of local structure tensors directly from the non-Cartesian coordinate system, thus avoiding deteriorated signal and noise characteristics caused by resampling. In many cases processing directly in the warped coordinate system is also less time-consuming. A geometrically correct tensor must obey certain transformation rules originating from fundamental differential geometry. Subsequently, this fact also affects the tensor estimation. As the local structure tensor is estimated using filters, a change of coordinate system also change the shape of the spatial support of these filters. Implications and limitations brought on by sampling require the filter design criteria to be adapted to the coordinate system.

    Place, publisher, year, edition, pages
    Springer Berlin/Heidelberg, 2007
    Series
    Lecture Notes in Computer Science, ISSN 0302-9743 (print), 1611-3349 (online) ; 4522
    National Category
    Signal Processing
    Identifiers
    urn:nbn:se:liu:diva-13023 (URN)10.1007/978-3-540-73040-8_96 (DOI)000247364000096 ()978-3-540-73039-2 (ISBN)978-3-540-73040-8 (ISBN)
    Conference
    15th Scandinavian Conference, SCIA 2007, Aalborg, Denmark, June 10-14, 2007
    Available from: 2008-03-13 Created: 2008-03-13 Last updated: 2015-10-08Bibliographically approved
    3. Efficient 3-D Adaptive Filtering for Medical Image Enhancement
    Open this publication in new window or tab >>Efficient 3-D Adaptive Filtering for Medical Image Enhancement
    2006 (English)In: 3rd IEEE International Symposium on Biomedical Imaging: Nano to Macro, 2006., IEEE , 2006, 996-999 p.Conference paper, Published paper (Refereed)
    Abstract [en]

    Tensor based orientation adaptive filtering, an explicit methodology for anisotropic filtering, constitutes a flexible framework for medical image enhancement. The technique features post-filtering steerability and allows user interaction and direct control over the high-frequency contents of the signal. A new class of filters for local structure analysis together with filter networks significantly lowers the complexity to meet the requirements of computation time for clinical use, while maintaining accuracy. In this paper the technique is applied to low-dose CT-images, magnetic resonance angiography and T2-weighted MRI.

    Place, publisher, year, edition, pages
    IEEE, 2006
    Series
    International Symposium on Biomedical Imaging. Proceedings, ISSN 1945-7928
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13024 (URN)10.1109/ISBI.2006.1625088 (DOI)000244446000252 ()0-7803-9576-X (ISBN)
    Conference
    3rd IEEE International Symposium on Biomedical Imaging: Nano to Macro, 6-9 April 2006, Arlington, VA, USA
    Available from: 2008-03-13 Created: 2008-03-13 Last updated: 2014-01-31Bibliographically approved
    4. Approximate Spectral Factorization for Design of Efficient Sub-Filter Sequences
    Open this publication in new window or tab >>Approximate Spectral Factorization for Design of Efficient Sub-Filter Sequences
    2008 (English)Manuscript (preprint) (Other (popular science, discussion, etc.))
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13025 (URN)
    Available from: 2008-03-13 Created: 2008-03-13 Last updated: 2015-06-02
    5. Filter Networks for Efficient Estimation of Local 3-D Structure
    Open this publication in new window or tab >>Filter Networks for Efficient Estimation of Local 3-D Structure
    2005 (English)In: IEEE International Conference on Image Processing (ICIP). 11-14 Sept, Genoa, Italy, 2005, Vol. 3, 573-576 p.Conference paper, Published paper (Refereed)
    Abstract [en]

    Linear filtering is a fundamental operation in signal processing, but for multidimensional signals the practical use is severely limited by the computer power available. Decomposition of filters into a layered structure of sparse subfilters, i.e. a filter network, significantly reduces the number of multiplications required for each data sample. A filter network, here used for phase invariant estimation of local 3-D structure, provides a flexible solution for linear filtering, especially suited for applying a set of filters on signals of higher dimensionality. The filter network presented, is twice as efficient as convolution based on the fast Fourier transform (FFT) and outperforms standard convolution by a factor exceeding 50 in terms of multiplications and additions performed.

    Keyword
    filter design, filter network, sparse filters, efficient filtering, local structure
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13026 (URN)10.1109/ICIP.2005.1530456 (DOI)
    Available from: 2008-03-13 Created: 2008-03-13 Last updated: 2013-08-28
    6. A Graph Representation of Filter Networks
    Open this publication in new window or tab >>A Graph Representation of Filter Networks
    2005 (English)In: Scandinavian Conference on Image Analysis (SCIA). Joensuu, Finland, 2005, 1086-1095 p.Conference paper, Published paper (Refereed)
    Abstract [en]

    Filter networks, i.e. decomposition of a filter set into a layered structure of sparse subfilters has been proven successful for e.g. efficient convolution using finite impulse response filters. The efficiency is due to the significantly reduced number of multiplications and additions per data sample that is required. The computational gain is dependent on the choice of network structure and the graph representation compactly incorporates the network structure in the design objectives. Consequently the graph representation forms a framework for searching the optimal network structure. It also removes the requirement of a layered structure, at the cost of a less compact representation.

    Keyword
    filters, orientation_frequency_phase, tensors, CMIV
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13027 (URN)
    Available from: 2008-03-13 Created: 2008-03-13 Last updated: 2013-08-28
  • 36.
    Jonson, Henrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Newton Method for Solving Non-Linear Optimal Control Problems with General Constraints1983Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Optimal control of general dynamic systems under realistic constraints on input signals and state variables is an important problem area in control theory. Many practical control problems can be formulated as optimization tasks, and this leads toa significant demand for efficient numerical solution algorithms.

    Several such algorithms have been developed, and they are typically derived from a dynamic programming view point. In this thesis a differentapproach is taken. The discretetime dynamic optimization problem is formulated as a static one, with the inputs as free variables. Newton's approach to solving such a problem with constraints, also known as Wilson's method, is then consistently pursued, anda algorithm is developed that isa true Newton algorithm for the problem, at the same time as the inherent structure is utilized for efficient calculations. An advantage with such an approach is that global and local convergence properties can be studied in a familiar framework.

    The algorithm is tested on several examples and comparisons to other algorithms are carried out. These show that the Newton algorithm performs well and is competitive with other methods. lt handles state variable constraints in a direct and efficient manner, and its practical convergence properties are robust.

    A general algorithm for !arge scale static problems is also developed in the thesis, and it is tested on a problem with load distribution in an electrical power network.

  • 37.
    wang, Daqin
    et al.
    Glorious Sun School of Business and Management, Donghua University, Shanghai, China.
    Tang, Ou
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, The Institute of Technology.
    Zhang, Lihua
    School of Economics and Management, Tongji University, Shanghai, China.
    A note on the rationing policies of multiple demand classes with lost sales2015In: International Journal of Production Economics, ISSN 0925-5273, E-ISSN 1873-7579, Vol. 165, 145-154 p.Article in journal (Refereed)
    Abstract [en]

    We study inventory rationing in a system with multiple demand classes and lost sales. It is assumed to have at most one outstanding order, resulting in two periods in an order cycle separated by the time of order release. We review the most related work by Melchiors (2001, PhD Thesis, University of Aarhus; 2003, International Journal of Production Economics 81-82, 461-468), and find that the existing approximated and optimal policies are not easy to obtain due to computational complexity. Also as the rationing issue before order release is not well addressed in literature, in this paper we have proved the static rationing being optimal. Furthermore in such a system with two distinct periods, the optimal rationing policy is a combination of a dynamic policy during the replenishment lead time and a static policy before order release. In order to make the rationing policies to be readily used in practice, we introduce two approximated methods for calculating the rationing levels in two periods, respectively. The results, in particular the combination of static and dynamic rationing, outperform the existing approximations in literature. In addition, the computation is obviously simplified due to the efficient algorithm of dynamic rationing and the explicit expressions of static rationing.

  • 38.
    Hauck, Shahram
    et al.
    Linköping University, Department of Science and Technology.
    Gooran, Sasan
    Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Faculty of Science & Engineering.
    A novel method to determine register variation of a press by a densitometry tool2015In: Journal of Print and Media Technology Research, ISSN 2223-8905, Vol. 4, no 2, 95-102 p.Article in journal (Refereed)
    Abstract [en]

    The print quality of a printing machine highly depends on good register variation values. The measuring of register variation is very important for putting a multicolor press in operation or for its repair and service. The manufacturers of print presses also need the evaluation of register variation to develop new products. The current industry standard method for measuring the register variation is based on image processing, which is a very expensive method. It was a great demand to determine the register variation by an alternative and affordable technique. In the present paper we introduce a new method to determine the register variation based on densitometry. In order to create a new method, a special color test target has been designed. The input of the method is the densitometric measurement values, and its output is the register variation value. The results of the method have been compared with those of an image processing method and the correlation coefficient between the results is almost 0.9. Since in the proposed method only a densitometer is needed, it can be considered as a very inexpensive alternative to the image processing methods. The results were also demonstrated to different specialists of a manufacturer of print press and received very positive feedback.

  • 39.
    Nielsen, Isak
    et al.
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Axehill, Daniel
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    A Parallel Riccati Factorization Algorithm with Applications to Model Predictive Control2014Report (Other academic)
    Abstract [en]

    Model Predictive Control (MPC) is increasing in popularity in industry as more efficient algorithms for solving the related optimization problem are developed. The main computational bottle-neck in on-line MPC is often the computation of the search step direction, \ie the Newton step, which is often done using generic sparsity exploiting algorithms or Riccati recursions. However, as parallel hardware is becoming increasingly popular the demand for efficient parallel algorithms for solving the Newton step is increasing. In this paper a tailored, non-iterative parallel algorithm for computing the Riccati factorization is presented. The algorithm exploits the special structure in the MPC problem, and when sufficiently many processing units are available, the complexity of the algorithm scales logarithmically in the prediction horizon. Computing the Newton step is the main computational bottle-neck in many MPC algorithms and the algorithm can significantly reduce the computation cost for popular state-of-the-art MPC algorithms.

  • 40.
    Chisalita, Ioan
    et al.
    Linköping University, Department of Computer and Information Science, IISLAB - Laboratory for Intelligent Information Systems. Linköping University, The Institute of Technology.
    Shahmehri, Nahid
    Linköping University, Department of Computer and Information Science, IISLAB - Laboratory for Intelligent Information Systems. Linköping University, The Institute of Technology.
    A peer-to-peer approach to vehicular communication for the support of traffic safety applications2002In: 5th IEEE Conference on Intelligent Transportation Systems, 2002, 336-341 p.Conference paper (Refereed)
    Abstract [en]

    More than half a million casualties are due to traffic accidents each year. Therefore, there is a high demand for innovative technologies focused on collision warning and collision avoidance. Among such technologies, the inter-vehicle communication and the vehicle-to-road communication are considered to have extensive potential for supporting the safety systems located within a vehicle. In this paper we propose a new approach to vehicular communication. We designed a safety-oriented vehicular communication, built around the concept of mobile ad-hoc peer-to-peer (P2P) networking. The merging between ad-hoc connectivity and P2P paradigm facilitates the development of a vehicular network characterized by self-organization, fault-tolerance, scalability, shareable resources and services, cooperation, cases of interconnection and cost efficiency. These characteristics recommend the communication proposed here as an efficient method for providing safety-relevant data for safety systems installed in vehicles.

  • 41.
    You, Lei
    et al.
    Qingdao University, Peoples R China.
    Lei, Lei
    Linköping University, Department of Science and Technology. Linköping University, Faculty of Science & Engineering.
    Yuan, Di
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, Faculty of Science & Engineering. University of Maryland, MD USA.
    A Performance Study of Energy Minimization for Interleaved and Localized FDMA2014In: 2014 IEEE 19TH INTERNATIONAL WORKSHOP ON COMPUTER AIDED MODELING AND DESIGN OF COMMUNICATION LINKS AND NETWORKS (CAMAD), IEEE , 2014, 16-20 p.Conference paper (Refereed)
    Abstract [en]

    Optimal channel allocation is a key performance engineering aspect in single-carrier frequency-division multiple access (SC-FDMA). It is of significance to consider minimum sum power (Min-Power), subject to meeting specified users demand, since mobile users typically employ battery-powered handsets. In this paper, we prove that Min-Power is polynomial-time solvable for interleaved SC-FDMA (IFDMA). Then we propose a channel allocation algorithm for IFDMA, which is guaranteed to achieve global optimum in polynomial time. We numerically compare the proposed algorithm with optimal localized SC-FDMA (LFDMA) for Min-Power. The results show that LFDMA outperforms IFDMA in the maximal supported user demand. When the user demand can be satisfied in both LFDMA and IFDMA, LFDMA performs slightly better than IFDMA. However MinPower is polynomial-time solvable for IFDMA whereas it is not for LFDMA.

  • 42.
    Vilhelmsson, Andreas
    et al.
    Nordic School Public Heatlh, Sweden.
    Svensson, Tommy
    Linköping University, Department of Behavioural Sciences and Learning, Education and Sociology. Linköping University, Faculty of Arts and Sciences.
    Meeuwisse, Anna
    Lund University, Sweden.
    A Pill for the Ill? Patients’ Reports of Their Experience of the Medical Encounter in the Treatment of Depression2013In: PLoS ONE, ISSN 1932-6203, Vol. 8, no 6Article in journal (Refereed)
    Abstract [en]

    Background

    Starting in the 1960s, a broad-based patients’ rights movement began to question doctors’ paternalism and to demand disclosure of medical information, informed consent, and active participation by the individual in personal health care. According to scholars, these changes contributed to downplay the biomedical approach in favor of a more patient-oriented perspective. The Swedish non-profit organization Consumer Association for Medicines and Health (KILEN) has offered the possibility for consumers to report their perceptions and experiences from their use of medicines in order to strengthen consumer rights within the health care sector.

    Methodology

    In this paper, qualitative content analysis was used to analyze 181 KILEN consumer reports of adverse events from antidepressant medications in order to explore patients’ views of mental ill health symptoms and the doctor-patient interaction.

    Principal Findings

    Overall, the KILEN stories contained negative experiences of the patients’ medical encounters. Some reports indicated intense emotional outrage and strong feelings of abuse by the health care system. Many reports suggested that doctors and patients had very different accounts of the nature of the problems for which the patient was seeking help. Although patients sought help for problems like tiredness and sleeplessness (often with a personal crisis of some sort as a described cause), the treating doctor in most cases was exceptionally quick in both diagnosing depression and prescribing antidepressant treatment. When patients felt they were not being listened to, trust in the doctor was compromised. This was evident in the cases when the doctor tried to convince them to take part in medical treatment, sometimes by threatening to withdraw their sick-listing.

    Conclusions

    Overall, this study suggests that the dynamics happening in the medical encounter may still be highly affected by a medical dominance, instead of a patient-oriented perspective. This may contribute to a questionable medicalization and/or pharmaceuticalization of depression.

  • 43.
    Malik, A
    et al.
    Lund University.
    Abdulhamid, H
    Lund University.
    Pagels, J
    Lund University.
    Rissler, J
    Lund University.
    Lindskog, M
    Lund University.
    Nilsson, P
    Lund University.
    Bjorklund, Robert
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Jozsa, P
    Volvo Technology Corp.
    Visser, J
    Ford Motor Co.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Sanati, M
    Lund University.
    A Potential Soot Mass Determination Method from Resistivity Measurement of Thermophoretically Deposited Soot2011In: AEROSOL SCIENCE AND TECHNOLOGY, ISSN 0278-6826, Vol. 45, no 2, 284-294 p.Article in journal (Refereed)
    Abstract [en]

    Miniaturized detection systems for nanometer-sized airborne particles are in demand, for example in applications for onboard diagnostics downstream particulate filters in modern diesel engines. A soot sensor based on resistivity measurements was developed and characterized. This involved generation of soot particles using a quenched co-flow diffusion flame; depositing the particles onto a sensor substrate using thermophoresis and particle detection using a finger electrode structure, patterned on thermally oxidized silicon substrate. The generated soot particles were characterized using techniques including Scanning Mobility Particle Sizer for mobility size distributions, Differential Mobility Analyzer-Aerosol Particle Mass analyzer for the mass-mobility relationship, and Transmission Electron Microscopy for morphology. The generated particles were similar to particles from diesel engines in concentration, mobility size distribution, and mass fractal dimension. The primary particle size, effective density and organic mass fraction were slightly lower than values reported for diesel engines. The response measured with the sensors was largely dependent on particle mass concentration, but increased with increasing soot aggregate mobility size. Detection down to cumulative mass as small as 20-30 mu g has been demonstrated. The detection limit can be improved by using a more sensitive resistance meter, modified deposition cell, larger flow rates of soot aerosol and modifying the sensor surface.

  • 44.
    Hedborg, Julia
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    A Printed Biosensor Based on an Organic Electrochemical Transistor with Mediated Gate Electrode2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Biosensor technology is an expanding field of research and there is a great market demand for low-cost disposable sensors. The aim of this project was to come up with a printed, disposable biosensor for glucose based on an organic electrochemical transistor (OECT). The organic semiconductor PEDOT:PSS was used as the material for the transistor channel and the gate electrode was made of carbon bulk modified with the different redox mediators potassium ferricyanide and ferrocene and the catalyst cobalt phthalo cyanine (CoPC) respectively. The enzyme glucose oxidase, that oxidases glucose, was used as sensing element and was immobilised on top of the gate electrodes. The sensor was fabricated with screen-printing, a low-cost technique that offers high throughput and is robust, simple and flexible. The gate electrodes were evaluated with cyclic voltammetry and chronoamperometry before integrated in the transistor device. The results showed that electrodes containing CoPC could detect hydrogen peroxide, a product in the reaction between glucose and the enzyme. Ferricyanide-electrodes showed good results regarding the activity of the mediator but no good results were achieved for the ferrocene-mediated electrodes. Transistor devices with CoPCmediated electrodes gave a response for 1mM hydrogen peroxide at 0.55V with good reproducibility, but the sensitivity needs to be further investigated. Transistor measurements with ferricyanide-mediated gates at 0.25V and glucose oxidase indicated that the glucose sensing works with these electrodes as well, but more measurements are needed. It was also concluded that the geometry of the transistor device had an influence on the relative response for the sensor, and a long channel proved to be better than a wide. The method used to fabricate the sensor offers great variation options and few production steps and the mediator approach enables inexpensive material costs.

  • 45.
    Karlsson, Magnus
    Linköping University, Department of Mechanical Engineering, Energy Systems. Linköping University, The Institute of Technology.
    A pulp and paper mill in the deregulated electricity market: strategies for electricity productionManuscript (preprint) (Other academic)
    Abstract [en]

    The deregulated electricity market has changed the prerequisites for the different actors in the market, both electricity producing companies and electricity purchasers. Companies may purchase electricity directly on the spot market and/ or use different derivatives, such as forwards and futures, as hedging instruments. There are various strategies for acting in the market and this paper explores alternative strategies for a Swedish board mill where hedging contracts to secure the price of electricity cover part of the electricity demand. The remaining demand is purchased on the spot market or produced on site. The back-pressure turbines on site are subject to possible changes in order to determine whether it is profitable to make additional investments aimed at reducing costs.

    Producing electricity close to the demand is a favourable alternative due to reduced losses in the grid and a lesser risk of power failure. Using back-pressure turbines on site meets these requirements and may also help to reduce the risk of power shortages. In certain situations, offering electricity production when there is a lack of electric power in the national grid is a possible alternative aimed at increasing income.

    The result shows that the choice of hedging strategy strongly influences the possibility of reducing costs. It is also shown that the different hedging strategies depend on factors such as the amount of electricity produced on site and the spot price.

  • 46.
    Pedersen, Kristina
    et al.
    University of Aarhus, Denmark .
    Wiechec, Emilia
    University of Aarhus, Denmark .
    Madsen, Bo Eskerod
    University of Aarhus, Denmark .
    Overgaard, Jens
    Aarhus University Hospital, Denmark .
    Hansen, Lise Lotte
    University of Aarhus, Denmark .
    A simple way to evaluate self-designed probes for tumor specific Multiplex Ligation-dependent Probe Amplification (MLPA)2010In: BMC Research Notes, ISSN 1756-0500, Vol. 3Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    The Multiplex Ligation-dependent Probe Amplification (MLPA) is widely used for analysis of copy number variations (CNVs) in single or multiple loci. MLPA is a versatile methodology and important tool in cancer research; it provides precise information on increased or decreased copy number at specific loci as opposed to loss of heterozygosity (LOH) studies based upon microsatellite analysis. Pre-designed MLPA kits and software are commercially available to analyze multiple exons, genes, and genomic regions. However, an increasing demand for new gene specific assays makes it necessary to self-design new MLPA probes for which the available software may not be applicable. During evaluation of new self-designed reference probes, we encountered a number of problems, especially when applying the MLPA methodology to tumor samples.

    FINDINGS:

    DNA samples from 48 unaffected individuals and 145 breast cancer patients were used to evaluate 11 self-designed MLPA probes and determine the cut-off values for CNV, before applying the MLPA probes to normalize the target probes in a cohort of affected individuals. To test the calculation strategy, three probes were designed to cover regions in Regulator of G-protein Signaling 8 (RGS8), which we previously have identified as being affected by allelic imbalance by LOH analysis across RGS8 in the cohort comprising 145 breast tumors. Agreement between the LOH results and the results obtained by each of the three MLPA probes in RGS8 was found for 64%, 73%, and 91%, of the analyzed samples, respectively.

    CONCLUSION:

    Here, we present a straightforward method, based upon the normalization pattern in both unaffected and affected individuals, to evaluate self-designed reference probes and to calculate CNV for the MLPA assay with specific focus on the difficulties when analyzing tumor DNA.

  • 47.
    Lindkvist, Louise
    et al.
    Linköping University, Department of Management and Engineering, Manufacturing Engineering.
    Erik, Sundin
    Linköping University, Department of Management and Engineering, Manufacturing Engineering.
    A stepwise method towards products adapted for remanufacturing2016In: INTERNATIONAL DESIGN CONFERENCE - DESIGN 2016: Dubrovnik - Croatia, May 16 - 19, 2016, 2016Conference paper (Refereed)
    Abstract [en]

    Remanufacturing is an important component of a resource-efficient manufacturing industry [see e.g. Rose and Ishii 1999; Steinhilper 1998; Sundin and Lee 2011]. By keeping components and their embodied material in use for a longer period of time, significant energy use and emissions to air and water (e.g. CO2 and SO2) can be avoided. According to Sundin and Lee [2011], environmental comparisons of remanufacturing versus new manufacturing and/or material recycling show environmental benefits for remanufacturing. This is due to alleviation of depletion of resources, reduction of global warming potential, and better chances to close the loop for safer handling of toxic materials [Sundin and Lee 2011]. In addition to its environmental benefits, remanufacturing provides opportunities for the creation of highly skilled jobs and economic growth.

     

    In order to make remanufacturing businesses more beneficial, product information should be accessible for the remanufacturing personnel and the products should be adapted for the remanufacturing process [Sundin and Bras 2005]. Although previous research identified information that could be fed back to the design phase from remanufacturing [e.g. Lindkvist and Sundin 2012] (see Table 1), such information is not often available in the design phase [Lindkvist and Sundin 2015]. Design for remanufacturing (DfRem) aims at facilitating the remanufacturing process so that e.g. disassembly, cleaning, reprocessing and reassembly are facilitated [Sundin and Bras 2005]. However, products are often not designed for remanufacture [Sundin and Bras 2005; Hatcher et al. 2011], although there do exist guidelines for design for remanufacturing [see e.g. Charter and Gray 2008, Sundin and Bras 2005].

     

    Successful integration of DfRem requires support on a strategic as well a tactical level, i.e. both what to do and how to do it [Yang et al. 2014]. Further, Hatcher et al. [2014] point out a gap in research regarding the operational factors influencing DfRem integration into the design process. In their findings, external factors such as customer demand and internal factors such as the OEM-remanufacturer relationship were identified. This paper addresses the combination of the strategic and tactical approaches, targeting the internal factors affecting DfRem integration into the design process. The proposed method is directed at companies that include both design and remanufacturing in their operations, and specifically supports integration of information from remanufacturing into the design process in order to better adapt products for remanufacturing. 

  • 48.
    Grubbström, Robert W.
    et al.
    Linköping University, Department of Production Economics. Linköping University, The Institute of Technology.
    Wang, Zhiping
    Linköping University, Department of Production Economics. Linköping University, The Institute of Technology.
    A stochastic model of multi-level/multi-stage capacity-constrained production–inventory systems2003In: International Journal of Production Economics, ISSN 0925-5273, Vol. 81-82, 483-494 p.Article in journal (Refereed)
    Abstract [en]

    A great deal of research has been done on capacity-constrained production–inventory systems, most of which concerns deterministic demand situations and single-product systems. In this paper we present a model of a multi-level capacity-constrained system when external demand is stochastic. Unlike the traditional total cost objective, adopted in the vast majority of capacity-constrained production–inventory models, the (expected) Net Present Value is here used as the objective function. Dynamic programming is chosen as the solution procedure. Numerical examples are given to explain the model and to illustrate features when changing available capacity.

    The Laplace transform together with input–output analysis are employed as tools to construct the model. This approach has been used in previous research to formulate a theoretical base for Material Requirements Planning (MRP) systems.

    The paper provides a further argument for the use of transforms in combination with matrix representations of product structures and capacity requirements, and it extends previous theory in the direction of capacity considerations combined with uncertainty in external demand. Dynamic programming is also shown to be a practical method for the multi-stage optimisation involved.

    The numerical examples further illustrate, for instance, the natural propensity for subordinate items to be lot sized in a more lumpy way than their parents, and also how the marginal benefit of capacity increments follows the law of diminishing returns. Also comparisons are made with solutions from the deterministic equivalence model, using average demand as a proxy.

  • 49.
    Borén, Sven
    et al.
    Department of Strategic Sustainable Development, Blekinge Institute of Technology, 37179 Karlskrona, Sweden.
    Nurhadi, Lisiana
    Department of Strategic Sustainable Development, Blekinge Institute of Technology, 37179 Karlskrona, Sweden.
    Ny, Henrik
    Department of Strategic Sustainable Development, Blekinge Institute of Technology, 37179 Karlskrona, Sweden.
    Robért, Karl-Henrik
    Department of Strategic Sustainable Development, Blekinge Institute of Technology, 37179 Karlskrona, Sweden.
    Broman, Göran
    Department of Strategic Sustainable Development, Blekinge Institute of Technology, 37179 Karlskrona, Sweden.
    Trygg, Louise
    Linköping University, Department of Management and Engineering, Energy Systems. Linköping University, Faculty of Science & Engineering.
    A strategic approach to sustainable transport system development – part 2: the case of a vision for electric vehicle systems in southeast Sweden2017In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 140, 62-71 p.Article in journal (Refereed)
    Abstract [en]

    Electric vehicles seem to offer a great potential for sustainable transport development. The Swedish pioneer project GreenCharge Southeast is designed as a cooperative action research approach that aims to explore a roadmap for a fossil-free transport system by 2030 with a focus on electric vehicles. In the first paper of this tandem publication, the authors propose a new generic process model embedding the Framework of Strategic Sustainable Development. The purpose of applying it in an action-research mode as described in this paper was twofold: (i) to develop a vision for sustainable regional transport and a coarse roadmap towards that vision, and, while doing so, (ii) get additional empirical experiences to inform the development of the new generic process model. Experts from many sectors and organizations involved in the GreenCharge project provided vital information and reviewed all planning perspectives presented in Paper 1 in two sequential multi-stakeholder seminars. The results include a sustainable vision for electric vehicle systems in southeast Sweden within a sustainable regional transport system within a sustainable global society, as well as an initial development plan towards such a vision for the transport sector. The vision is framed by the universal sustainability principles, and the development plan is informed by the strategic guidelines, of the above-mentioned framework. Among other things, the vision and plan imply a shift to renewable energy and a more optimized use of areas and thus a new type of spatial planning. For example, the vision and plan implies a lower built-in demand for transport, more integrated traffic modes, and more multi-functional use of areas for energy and transport infrastructures, for example. Some inherent benefits of electric vehicles are highlighted in the vision and plan, including near-zero local emissions and flexibility as regards primary energy sources. The vision and plan also imply improved governance for more effective cross-sector collaboration to ensure coordinated development within the transport sector and between the transportation sector and other relevant sectors. Meanwhile, the new generic process model was refined and is ready to be applied and further tested in the GreenCharge project and in other projects within the transport sector as well as other sectors. The study confirmed that the new generic process model suggested in support of sustainable transport system and community development is helpful for giving diverse stakeholders, with various specialties and perspectives, a way of working that is goal-oriented and builds on effective, iterative learning loops and co-creation.

  • 50.
    Holmgren, Johan
    Linköping University, Department of Science and Technology, Communications and Transport Systems. Linköping University, The Institute of Technology.
    A strategy for increased public transport usage: The effects of implementing a welfare maximizing policy2014In: Research in Transportation Economics, ISSN 0739-8859, Vol. 48, 221-226 p.Article in journal (Refereed)
    Abstract [en]

    For a long time public transport has experienced a struggle against rising costs and increasing car ownership. So far, public transport appears to be on the losing side in terms of market shares. The aim if this paper is to investigate if a different policy could result in higher public transport usage and improved social welfare. In order to achieve this, a model, explaining public transport usage, public transport supply and costs, is estimated. The model is then used in order to simulate the outcome of an alternative policy of social welfare maximization. It is found that the current policy of the Swedish transport is not efficient in terms of maximizing welfare. In 2011, public transport fares should have been lower in 20 of 21 counties and the supply of vehicle kilometres should have been higher in 17 of 21 counties. Implementing a welfare maximizing policy would have increased the number of trips per capita by 17.2% in 2011 and by an average of 6.7% for the period 1986-2011.

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